


You Bet Your Aft

by blackgoliath



Category: The Transformers (IDW Generation One)
Genre: Forgive Me, M/M, Sticky Sexual Interfacing, also there's a similar bondage fic out there, and bondage, and kup proving how awesome he is, based off of a chromia/windblade comic, don't look at me, includes vibrators, p sure drawn by herzspalter but i'm bad with names, which i did not know until i'd already finished this so
Language: English
Status: Completed
Published: 2016-05-24
Updated: 2016-05-24
Packaged: 2018-06-10 10:07:00
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,555
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6952240
Author URL: https://archiveofourown.org/users/blackgoliath/pseuds/blackgoliath
Summary: <blockquote class="userstuff">
              <p>Springer questions Kup's ability in the berth; Kup sets out to prove him wrong.</p>
            </blockquote>





	You Bet Your Aft

**Author's Note:**

> i wrote this a while ago and have only just gained the courage to share so HERE YALL GO hope you have fun

“You? Good in the berth?” Springer laughed. “Maybe three million years ago, old man. You’d probably break a hip strut if you tried now!”

They were in the ship’s mess, the two of them, at a table off to the side by the door. They weren’t the only two in there – Topspin and Twin Twist were grabbing themselves some energon and Roadbuster sat by himself not far off – but Kup wasn’t really bothered if any of them heard what he and Springer were talking about. The crew was used to Kup and Springer’s weird, banter-filled conversations. He wasn’t sure how they’d gotten on this particular topic, and though he’d heard enough of Springer’s ‘old timer’ jokes that he usually ignored them, he wasn’t about to let a comment like that slide.

“I’m tellin’ the truth, kid. I had plenty of skills back in the day and they’ve only ripened with age.”

Springer snorted at that. “Oh, I’m sure, but can your spike even pressurize anymore?”

“You bet your aft it can!” He moved his cy-gar in his mouth, from one side to the other, and, leaning forward with a grin, added, “I can even prove it to you.”

Springer’s optic ridges rose. “Right here? You’re gonna whip it out right here?”

“ _No_ , you blockhead. I’m sayin’ I can prove I’ve still got it. In the berth.”

“Are you suggesting what I think you’re suggesting?” Springer’s tone was incredulous, but Kup could tell by the glint in his optics that he was interested. Springer was a bot in his prime, and he had a pretty healthy sexual appetite; it was common to see him taking random mechs back to his quarters whenever they were on shore leave. And, Kup thought, amused, the kid probably thought he was going to end up showing Kup a thing or two.

“I am,” Kup replied, leaning back again and crossing his arms. “That is, if you’re up to it. I get it if you’re too put off by a seasoned, experienced bot like myself.”

“Ha! You’re on!” Springer even had the audacity to wink. “But don’t get upset if you don’t have it in you. Strenuous exercise can be rough on such old mechanisms, I understand–”

“Kid, I swear to Primus.” Kup was still grinning as he shook his helm. “Meet me in my quarters later, then. After your shift.”

Springer smirked. “Sure.”

That was how, several cycles later, they’d ended up with Springer on Kup’s berth, special restraints tied to the berth posts keeping his servos up above his helm. Kup had spent some time beforehand sifting through the secret little trunk he kept among his possessions, deciding what exactly he wanted to do with Springer, and he’d come up with a pretty good plan. The trunk was now sitting on the small side table next to the berth, open and waiting, as Kup swung a leg over Springer’s waist and straddled him.

“I have to say, I didn’t expect you to have anything like this,” Springer admitted, grinning up at Kup. “But I still don’t think you can get it up.”

“I told you I’d prove I could do that an’ more, so stop bein’ so impatient.” Kup mirrored Springer’s expression as he leaned in, automatically shifting the cy-gar to the very corner of his mouth before pressing his lips to Springer’s. Springer chuckled against Kup’s lips and said something he couldn’t really hear; when Kup momentarily pulled back Springer repeated himself.

“It’s funny, kissing you with that thing in your mouth.”

“What thing?” It took an astro-second for the weight of the cy-gar on his glossa to register. “Oh, that.” He plucked it from his mouth and set it on the side table next to the open trunk.

“Wait,” Springer said quickly, “You don’t have to take it out, I just thought it was funny-”

“You want me to chew on that thing _and_ frag your brains out?” Kup asked, chuckling. “That’s a weird request.”

“I just thought, uh, maybe you need it..?”

“For what?” He gave Springer an odd look. “I don’t have it in my mouth all the time, yanno. I’d choke on the damn thing if I slept with it between my teeth.”

“I guess, if you’re sure,” Springer said, but he still looked uncertain, until Kup lightly ran a digit tip along a transformation seam in Springer’s side and felt the bot beneath him give a little shiver. He smiled.

“Don’t worry about it.” Kup kissed him again, letting his servos roam that broad chassis, tracing transformation seams and breaks in Springer’s plating, dipping his digits beneath to pluck at the sensitive wiring there. He could hear Springer’s cooling fans kick in as he worked his servos lower, and he grinned at how easily the triple changer was getting worked up. When he reached Springer’s hips where he was sitting Kup moved, pressing his lips now to Springer’s neck cabling, shifting Springer’s knee struts apart with his own so he could kneel between them as he brought his mouth and servos further down. His servos came to rest on the joint of Springer’s thighs where they met his pelvis, thumb digits slipping between the plating right at the junction to rub the soft protoform under it. Springer actually sighed at that, tilting his hips up into Kup’s touch, and against Springer’s chassis plating Kup grinned.

“Okay,” Springer said, and his heavier venting was evident in his voice, “Maybe you’re better at this than I thought.”

“Throwin’ in the towel already? I barely started.” Kup slid his glossa into a transformation seam low on Springer’s abdomen at the same time as he pressed his thumbs deeper beneath Springer’s plating, and Springer moaned, frame arching.

“No, no, not at all.” Kup looked up to see Springer smirking, even with the small sparks beginning to scurry across his plating from the excess charge running through his circuits. “Still haven’t proved you can get pressurized.”

“I told ya not to be so impatient, but if you’re gonna insist…” Kup firmly palmed Springer’s pelvic plating, which was, he noticed, very warm beneath his digits. Springer shuddered. “Open up, and if anything gets too much, you lemme know.”

Springer nodded, and apparently didn’t need to be told twice; the plating slid back, revealing a fully erect spike (even bigger than Kup had thought, damn this kid was packing) and a valve that was already glistening with lubricant. Kup felt his own spike begin to push uncomfortably against his plating, but ignored it for now as he swiped the pad of a thumb up the ridges of Springer’s, earning another soft moan.

“Doesn’t take much to get you goin’, eh?”

“N-No, it’s just, I–” Springer’s mouth moved but nothing else came out; he couldn’t seem to find a response that didn’t either compliment Kup’s skills again or agree with what Kup had just said, so instead he huffed and said nothing. Kup chuckled lightly as he got up, rifling through the trunk on the side table before he found what he was looking for.

Springer lifted himself as much as he could to see what was in Kup’s servos. “What’s that?”

“You’ll see.” Kup took the small, silver rectangular object, grabbed an adhesive (but safe, and painless; he knew what he was doing) tape roll and took a sliver to tape the object against Springer’s exterior node. Springer shifted a little bit at the pressure, craning his neck cabling as he tried to see what Kup was doing.

“It feels weird.”

“It won’t in an astro-sec.” There was a button on the front (and an intensity slider on the side, which Kup had already adjusted) and when he pushed it the vibrator came to life, buzzing against Springer’s node. The triple changer fidgeted a little at the sudden sensation, while Kup sat back, letting his own panel click out of view, his spike sliding up, just as pressurized as Springer’s, from its casing.

“Guess you did prove me wrong,” Springer said, still going for cocky. “But is this little thing your big trick? I can barely feel it.”

“This ain’t even scratchin’ the surface, kid.” Kup leaned against the berth posts on the other side of the berth, supporting himself as he slowly stroked a servo along his own spike. Springer watched him, optics hungry, legs spread invitingly.

“Come on, you’re not just gonna sit over there, are you? I take back that one thing I said about you being good at this.”

Kup chuckled again, the sound edging on breathy as he kept up the attention on his spike. “The more you complain, the more I think you ain’t really ever had a good fraggin’, kid. It’s best when you take your time.”

“But I want it _now_.” Tiny bright blue sparks, the same color as Springer’s optics, were dancing erratically along his plating. The vibrator continued to buzz and Springer slowly began to rock his hips, tilting his helm to the side and muffling the sounds he’d started making in his shoulder. Kup watched from where he sat, his servo still moving slow, and after another klik he couldn’t keep himself from saying,

“Guess you’re startin’ to feel it.”

“I-” Springer groaned, rocking faster, as if that would help in any way. “Ahh, it’s – it’s a-alright, I guess, b-but – I’ve had – b-better -” He cut himself off as his first overload hit him suddenly, and he let out nothing but a sharp gasp as the outer edges of his valve visibly spasmed. His spike, despite not having been touched, still had a small gush of transfluid spurting from the tip. Kup never took his optics off of Springer, and let out a quiet moan at the sight.

“Come on, K-Kup, you proved your p-point,” Springer whined, vibrator still going, his hips still thrusting at nothing though he was lifting himself further off the berth now in search of more stimulation. “You said….you were g-gonna frag my b-brains out…..so d-do it!”

“Not yet,” Kup said, vocalizer dropping an octave, though he hadn’t meant it to. Springer grunted in frustration and a few kliks later his frame shuddered and he keened as a second overload burst through him, plating tightening in a way obvious to even the most oblivious mech. Kup’s spike twitched in his servo. This was even better than he’d hoped it would be.

Springer was starting to writhe on the berth, the vibrator continuing its steady rhythmic buzz, pushing the triple changer straight through his overload and into the build of another charge. He wasn’t trying to stifle the moans now, the sounds slipping from his lips getting louder as he rolled his hip struts in time with the buzzing of the device pressed against his exterior node. Kup could see the steam drifting off of Springer’s hot plating into the cooler air of Kup’s quarters, see how his servos strained against the bonds Kup had put him in. He’d even begun whimpering, unintelligible sounds of need intermixed with “Oh Primus,” and “Kup, _please_ ,”. It was tempting, but Kup wanted him to suffer a bit longer. He stayed where he was at the other end of the berth, servo working a little faster but not too much along his own spike, slowly letting his own charge build in his systems. He could go like this for a while.

But then Springer’s third overload hit, harder than the other two and Kup knew this because Springer actually _squirted_ , lubricant streaming from his valve and splattering across Kup’s abdomen and pelvis. Springer threw his helm back and straight up _screamed_ as it happened, and then it happened again, twice, three times before it stopped, Springer roiling in his bonds, gaining no pause from one overload to the next as the vibrator kept going. The difference was that Kup hadn’t expected that, hadn’t planned for that and he was crawling back up the berth between Springer’s twitching legs before he even thought about it.

He lifted Springer’s hip struts in his servos, dimly registering the triple changer’s nearly-sobbed “ _Finally_ ,” before he was pushing his spike into Springer’s soaking valve. It was so well lubricated that a Prime’s spike could have slid inside without any difficulty at all, but it was still tight and hot and the calipers clenching around him felt fraggin’ amazing.

“P-Primus, ahh, ahhhhhh K-Kup! Kup oh s-slag oh slag k-keep going I n-need – f-frag oh P-Primus–” Springer wasn’t even coherent anymore. Kup bent over him, no longer able to control himself either, sparks jumping from one frame to the other and metal clanging from the speed and strength with which Kup was thrusting into Springer’s valve. He had one servo pressed against the berth beside Springer’s helm, the other supporting Springer’s aft and he felt the younger bot’s legs tighten around his hip struts even as he shifted and angled himself to push deeper. Helm bent, vents coming in harsh pants and cooling fans competing with Springer’s for volume, Kup kept up his harsh pace until Springer bowed beneath him, frame rattling and mouth open in a wordless cry when his fourth overload exploded inside of him. This time his spike went too, transfluid bursting from the tip onto his own abdomen and his valve clenching so tightly around Kup that he couldn’t move if he’d tried, but that was fine because the pressure shoved Kup over the edge soon after. He held himself flush against Springer, spike up to the hilt inside that glorious, rippling heat. Finally Springer crashed back against the berth, frame trembling hard in the aftermath.

“P-Please….t-take….it o-off - “ His tone bordered almost on pain and despite his post-overload haze Kup acted quickly, pulling the vibrator away and tossing it aside. Springer groaned in relief and let his limbs go limp, Kup’s de-pressurizing spike popping out of his valve with a soft sucking sound.

“You alright, kid?” he asked, his own venting still coming rather quickly even as he reached up and untied Springer’s servos from the berth posts. Springer truly collapsed then, arms falling to his sides, pelvic plating slowly clicking back into place, though some fluids leaked out through the seams.

“Yeah…..y-yeah, I think so.”

Kup let himself drop down beside Springer, offlining his optics for an astro-second as he worked to regulate the heat pooling in his systems and the rough way he was venting. He heard something that made him online his optics and saw that Springer had turned his helm to look at him.

“Guess it…takes some time for you…to recover, huh?” Springer said, still panting, though he did manage a tired smirk. Kup couldn’t believe it. He at least was able to chuckle.

“Still proved you wrong.”

“Yeah. Guess you did.” Springer shifted closer, surprising Kup (who would have thought he didn’t have the energy to do more than lie there) and rested his forehelm against Kup’s.

“You said – uh. You said you had….other tricks, right?” Springer’s optics were offline, and his vents ghosted over Kup’s face. “I think. I think I want to see them. All of them.”

That was unexpected, but…..nice. Kup’s lip curled, and he gathered the energy to reach up and rest his servo on Springer’s cheek.

“Sure thing, kid. I’ll show you everything I got.”


End file.
